Answer:
2
Explanation:
Prophase II, metaphase II, anaphase II, telophase II.
The correct answer is option D, Temporal isolation
Temporal isolation is the mechanism which prevents the mating of closely related species living in the same ecosystem. Basically the reproductive barriers prevent these species from interbreeding. Temporal isolation is a prezygotic barrier that causes “time isolation” between the breeding period of two closely related species. The difference in time could be “difference in time of day”, “ difference in season of mating”, “difference in months” and in some cases “ difference in years”.
Answer:
Option (A)
Explanation:
The Precambrian represents the time period, right from the beginning of the earth to about 540 million years back. It is divided into 3 parts, namely the Hadean, the Archean and the Proterozoic. Throughout this geological time, vast changes have taken place on earth. The first life forms of about 3.8 billion years old, that existed on earth were the simple unicellular organisms, whose traces were only found at some particular places. These organisms were very small and are comprised of soft bodies, so they were affected by the earth's dynamic processes. The organisms in order to get fossilized must contain hard parts. Due to the presence of soft bodies, the organisms were not fossilized and so it took a long time to demarcate that the late Precambrian organisms were animal-like life.
hence, the correct answer is option (A).
Answer:
B. neuroglia.
Explanation:
Neuroglia, also called glial cells are cells that support neurons structurally and functionally.
There exists two broad classes of cells in the nervous system which are:
- Neurons
- Glia
The neurons process information while the glia support the neuron mechanically and metabolically.
In general, there are three main types of cells that make up the nervous system including the above two.